1. Field of the Invention
This invention relates to cartridges for electrostatic spraying apparatus, and more specifically to disposable cartridges for use in electrostatic spraying apparatus for cosmetic products.
2. Background Information
Traditionally most skin care or cosmetic products, such as lotions, perfumes, and make-up, for example, have been applied by a limited number of methods. For example, frequently they are simply applied by the hand of the user, who would spread or rub the product onto the skin with the fingers or with the aid of an application pad. These produces are also frequently sold in pump sprays or pre-pressurized aerosol containers, so as to have the product atomized and sprayed with the aid of a propellant gas.
More recently, electrostatic spraying devices have been developed for the application of personal care products, such as skin care and cosmetic products. However, many of these more recent apparatus can still be bulky and/or require bench top equipment and external electrical wiring, which can make them cumbersome or hard to use. A few portable hand-held electrostatic devices are also known, however these known electrostatic devices frequently require the product to be dispersed by the application of pressure by hand, or from a pre-pressurized container, with the aid of a propellant, such as a fluorocarbon, or chlorofluorocarbon, for example. Additionally, many known electrostatic spraying devices require the pouring of the product into a separate refillable container, which container is then connected to the spraying device by a hose or a dip tube.
Typically, the known application methods and apparatus have a number of drawbacks. For example, frequently these methods and devices are unable to deliver a desired target product flow rate with great accuracy and precision, thus resulting in uneven coverage and wasted product. These drawbacks can be particularly troublesome when applying cosmetics, such as foundation, for example. Applying too much foundation in an uneven manner can result in both excessive wasted amounts of potentially expensive cosmetics, as well as an unsatisfactory and unattractive final appearance of the skin to which the foundation is applied. For example, when all the skin is covered the natural skin tones cannot show through, and the user can feel like she is wearing a mask. Consequently, known application processes and products frequently make it difficult to adequately conceal skin flaws and yet create a finished "look" which is both natural in appearance and long lasting.
Additionally, some of the known electrostatic spraying devices do not adequately focus the electrical charge and/or insulate the product supply from the electrostatic charge. This can particularly be a problem when a two-phased product, such as a two-phased foundation, is used in the device, since some of these products can be prone to separation when electrostatic charge travels to the reservoir containing the supply of product.
Further, since many known electrostatic devices have containers or reservoirs, which continually need refilling with product, these containers can not only be inconvenient to refill, but can also be messy and thus require cleaning and maintenance by the user. Refilling can also result in a risk of contamination of the new product by residue, left in the container. Additionally, known electrostatic spraying devices typically have one spray nozzle which is repeatedly reused. After repeated and/or long-term use this single nozzle can be subject to clogging and contamination, thus also requiring maintenance and cleaning by the user. Additionally, many known nozzles are made of conductive material, which can result in the user accidentally touching the nozzle and thereby potentially shocking themselves or grounding the device.
Finally, in known electrostatic spraying devices, manufacturing problems and additional costs can result from the production of numerous separate pieces, such as separate electrodes, nozzles and insulators.